This will help in getting it tuned right and prevent the clipping. I would also included them in the design process, nit just in providing the labor. Get their thoughts. By doing the install, they are putting their name on it. They will want to make sure it performs up to your standards and resolve any areas of concern in the design, prior to the build.
The system will be installed by pro's
I would consider going with a single 12" in a ported enclosure. Both those amps you are considering, will yield the same 600W potential to a single 12 or dual 10. Although dual 10 give the edge in terms of surface area, ill take a single 12 in a ported enclosure.
and a extra 10" free air .
Id consider the new WS-220BT 4 zone controller. Allows for the bow to be a zone.
What are your thoughts here with 2 different 6 chnls?
to your direct questions:
1) can be with the right amp and speaker pairings. Just note that a crappy download or file stream can be the weak link in even the most expensive system.
2)Your 08 was likely wired with 12ga wire. As long as the ends can be clipped back a few inches to insure its good clean wire strands with no corrosion wicked down, then yes, no need to replace. However, if the ends are too short, dont look good, too small of a gauge or the insulated is compromised at the tower fold or foot where it passes through the deck, then replace.
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